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We captured single shot images of ZnO emission patterns originating from excitation with the EUV laser at Japan Atomic Energy Agency (JAEA). The EUV laser was focused to a spot size of 1~\mu \m on the ZnO crystal by a Fresnel Zone Plate (FZP). The FZP was shifted along the propagation direction of the EUV beam, essentially changing the spot size at the ZnO surface. The emission pattern was detected by a magnifier. The waist radii were determined from the fitting curve as 5.0~\mu \m along the horizontal axis and 4.7~\mu \m along the vertical axis. We also evaluated the spatial resolution of the magnifier, which consists of a Schwarzschild mirror, two lenses and a camera lens to be about 4~\mu \m. These results suggest that the ZnO crystal has sub-micron spatial resolution when used as an in-situ imaging device for the diagnostics of EUV/X-ray sources. [ABSTRACT FROM PUBLISHER]

We show that a hydrothermal method-grown ZnO is a potential material of an imaging device for soft X-ray laser diagnostics. The beam profile of a soft X-ray laser was evaluated by characterizing the exciton emission patterns of ZnO. The single shot image of emission patterns is clear enough to monitor the evolution of the beam radius around the focal point. By plotting the emission pattern radii at each position, the beam profile of the Ni-like Ag ion plasma laser was estimated from the waist radii as 29 \mum and 21 \mum in the horizontal and vertical axis, respectively. The divergence angle was estimated to be around 7.2 mrad and 11 mrad in the horizontal and vertical axis, respectively. The beam quality evaluated from the M^2 factor was 47 along the horizontal axis and 50 along the vertical axis. Spatial resolution of the magnifier was estimated to be 6 \mum and is expected to improve by optimizing the optics of the magnifier and using a telescope. Our results would enhance the use of ZnO as a high-spatial resolution in-situ imaging device that would play a crucial role in the development and application of soft X-ray light sources. [ABSTRACT FROM PUBLISHER]

The characteristics of an APLF80+3Ce scintillator are presented. Its sufficiently fast decay profile, low afterglow, and an improved light output compared to the recently developed APLF80+3Pr, were experimentally demonstrated. This scintillator material holds promise for applications in neutron imaging diagnostics at the energy regions of 0.27 MeV of DD fusion down-scattered neutron peak at the world's largest inertial confinement fusion facilities such as the National Ignition Facility and the Laser Mégajoule. [ABSTRACT FROM AUTHOR]

Abstract: Optical and scintillation properties of Pr-doped Li-glass, 20Al(PO3)3-80LiF:Pr 3%, have been studied for applications in neutron detection systems. Based on optical transmission and reflectivity, the absorption coefficient and refractive index were calculated from the Beer Lambert law. The absorption edge was apparently shifted to the longer wavelength from 160nm to 240nm due to 4f→5d transitions of Pr ions. The strong absorption peaks of praseodymium 4f→4f transitions were observed from 420nm to 500nm and around 590nm. The radio-luminescence spectrum excited by 241Am 5.5MeV α source was measured. Strong emission peaks were observed around 250nm. The α-ray excited pulse height spectrum and decay kinetics were also examined. Light yield was estimated to be 400±40 photons/5.5MeV α and the main component of the decay time was evaluated to be about 12ns. Furthermore, the pulse height spectrum of the glass excited by 252Cf neutrons was also measured, and the light yield was estimated to be 140±10 photons/neutron. [Copyright &y& Elsevier]

Abstract: A novel custom-developed scintillator for laser fusion diagnostics is reported. With the aim of diagnosing scattered neutrons from the imploded high-density fusion plasma, a fast response lithium-6 glass scintillator has been developed. Praseodymium, instead of the more widely-used cerium was chosen as the dopant. Sufficiently fast luminescence lifetime for scattered neutron diagnostics (<20ns) was experimentally observed, and the feasibility was successfully shown in laser-fusion experiments at the GEKKO XII facility of the Institute of Laser Engineering, Osaka University. [ABSTRACT FROM AUTHOR]

Abstract: We explore the potential of Pr- or Ce-doped 20Al(PO3)3–80LiF (APLF80+3Pr or +3Ce) scintillator to observe the lower edge of down-scattered neutron and discriminate fusion originated neutron from strong X-ray signals. APLF80+3Pr or +3Ce scintillator exhibits considerably fast decay profiles and negligible slow-decay components. Using these newly developed APLF80+3Pr or +3Ce scintillators, we have successfully observed fusion-originated neutron signal in the midst of strong X-ray-excited fluorescence in an integrated experiment using our 10kJ class GEKKO XII Nd-glass laser system. A sophisticated neutron detection system using APLF80+3Pr or 3Ce will be used for the first fast ignition experiment. [Copyright &y& Elsevier]